/*
 * Copyright (c) 2015, 2022, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.oracle.truffle.espresso.runtime.jimage.decompressor;

import java.nio.ByteBuffer;
import java.util.zip.DataFormatException;
import java.util.zip.Inflater;

import com.oracle.truffle.espresso.runtime.jimage.BasicImageReader;

final class ZipDecompressor implements ResourceDecompressor {
    public static final String NAME = "zip";

    @Override
    public String getName() {
        return NAME;
    }

    @Override
    public ByteBuffer decompress(StringsProvider reader, ByteBuffer content, long originalSize) {
        Inflater inflater = new Inflater();
        inflater.setInput(content);
        ByteBuffer output = ByteBuffer.allocate(Math.toIntExact(originalSize)).order(content.order());
        try {
            inflater.inflate(output);
        } catch (DataFormatException e) {
            throw new RuntimeException(e);
        }
        boolean finished = inflater.finished();
        inflater.end();
        if (!finished) {
            throw new RuntimeException("Unexpected end of zip data");
        }
        if (output.hasRemaining()) {
            BasicImageReader.LOGGER.warning("ZipDecompressor output was smaller than expected: " + output.remaining() + "bytes of output remaining");
        }
        return output.flip();
    }
}
